From: Brian McGahan (bmcgahan@internetworkexpert.com)
Date: Fri Oct 22 2004 - 13:48:27 GMT-3
No you do not need to exclude the router's address, nor does the
pool have to be made up of addresses that are directly connected. DHCP
is not enabled on a per interface basis, it is global to the router. If
the router receives a broadcast DHCP request from a source address of
0.0.0.0 it knows that the client is directly connected. All other
requests would come from relay agents, and the pool chosen would be
based on the source address that the relay request comes from. If this
was not the case you would need a DHCP server on every segment of the
network.
HTH,
Brian McGahan, CCIE #8593
bmcgahan@internetworkexpert.com
Internetwork Expert, Inc.
http://www.InternetworkExpert.com
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> -----Original Message-----
> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf
Of
> ccie2be
> Sent: Friday, October 22, 2004 7:26 AM
> To: Sasa Milic; ccielab@groupstudy.com
> Subject: Re: DHCP
>
> Hi Sasa,
>
> Thanks for getting back to me on this. I found out the other day why
my
> network and mask wouldn't work, but you say something else that's
contrary
> to what I thought - "Then exclude router interface's IP address".
>
> I thought dhcp was smart enough to know to "NOT offer it's interface
> address
> to dhcp clients" even if that address wasn't explicitly excluded.
>
> Am I mistaken about this?
>
> Thanks,Tim
>
>
> ----- Original Message -----
> From: "Sasa Milic" <smilic2@pexim.co.yu>
> To: "ccie2be" <ccie2be@nyc.rr.com>; <ccielab@groupstudy.com>
> Sent: Friday, October 22, 2004 6:32 AM
> Subject: Re: DHCP
>
>
> >
> > Your solution won't work. Besides being wrong for not
> > including/excluding required addresses, and wrong mask,
> > the problem that prevents your solution to work is that
> > none of router interfaces are covered by pool. That's
> > why you have to have pool 163.3.6.0 255.255.255.0 (it
> > will cover IP address of router interface, so that router
> > knows on what interface to run dhcp server). Then exclude
> > router interface's IP address and all other addresses
> > that are specified in requirements.
> >
> > Hope this helps.
> >
> > Sasa
> >
> >
> > ccie2be wrote:
> > >
> > > Hi guys,
> > >
> > > I need to configure dhcp to meet these requirements:
> > >
> > > Assign ip addresses from 163.3.6.128 thorugh 163.3.6.250
> > > Exclude ip address: 163.3.6.130
> > >
> > > My solution was like this:
> > >
> > > ip dhcp excluded-address 163.3.6.251 163.3.6.255
> > > ip dhcp excluded-address 163.3.6.130
> > > !
> > > ip dhcp pool ADDRESSES
> > > network 163.3.6.128 255.255.255.128 <-- Is this allowed?
> > >
> > > However, the "official" solution was like this:
> > >
> > > ip dhcp excluded-address 163.3.6.251 163.3.6.255
> > > ip dhcp excluded-address 163.3.6.130
> > > ip dhcp excluded-address 163.3.6.0 163.3.6.127
> > >
> > > ip dhcp pool ADDRESSES
> > > network 163.3.6.0 255.255.255.0
> > >
> > > So, the only difference between my solution and the official
solution
> was that
> > > I used a different subnet and mask and therefore shouldn't need to
> exclude
> > > host ip addresses from 0 to 127.
> > >
> > > I can't test this, so I was wondering if my solution would work
OK.
> > >
> > > Thanks, Tim
> > >
> > >
>
This archive was generated by hypermail 2.1.4 : Sat Nov 06 2004 - 17:11:51 GMT-3